What is Rtools?

• A collection of tools necessary for building R packages in Windows
• Available for download at http://cran.r-project.org/bin/windows/Rtools/

Download Rtools

• Select the .exe download link from the table that corresponds to your version of R
• Note: If you're not sure what version of R you have, open or restart R and it's the first thing that comes up in the console
• If you have the most recent version of R, you should select the most recent Rtools download (at the top of the chart)
• Once the download completes, open the .exe file to begin the installation

Install Rtools

• Unless you really know what you are doing, you should just go with the default selections at each step of the installation
• There are only two exceptions worth noting:
• If you already have Cygwin installed on your machine, you should follow the instructions given during installation (and linked to here: http://cran.r-project.org/bin/windows/Rtools/Rtools.txt)
• IMPORTANT: You should make sure that the box is checked to have the installer edit your PATH (see below).

Install devtools

• Once the Rtools installation completes, open RStudio
• Install the devtools R package if you have not previously done so
• If you aren't sure, enter find.package("devtools") in the console
• To install devtools, use install.packages("devtools")

Verify Rtools installation

• After devtools is done installing, load it using library(devtools)
• Then type find_rtools() as shown below
• This should return TRUE in the console if your Rtools installation worked properly